I'm curious what about people's thoughts are on a skill system where skills advance based on frequency of use, with the most-used skills increasing in proficiency and least-used skills actually going down in proficiency. I'm hoping this will be a more accurate system that will be more reflective of what the PCs actually do over the course of a game. In addition I'm hoping it will prompt players to use the full range of their skills.

To give this some background, in the current system I'm working on, the players selects a number of skills they are trained in, with each trained skill given an equal amount of skill points. Each skill point adds a % bonus to the skill. During the level-up process these skill points slowly shift around from least to most-used skills (with players keeping track of successful skill uses during gameplay). I'm hesitant to add a mechanic where characters simply lose training in a skill if it loses all its skill points. I would think that if you've received any kind of in depth training in a skill, you would still retain something from it, right?

The biggest pitfalls I can see is that players may spend more time trying to make pointless skill attempts to keep all their skills balanced or it will create one-dimensional characters if the PC just goes all out and only focuses on building up a few core skills. I've tried to eliminate the pointless skill attempts by stating that characters can only count "relevant skill uses" as actual uses and each would have to approved by the GM before a character can count it. I'm wondering if this won't set the GM & players up for frequent disagreements over what counts as a relevant skill use.

For this thread to continue, please set up and link to some external document that we can reference. It doesn't have to be your complete work, or even really anything more than what you have here. But it does need to be off-Forge. See the forum sticky thread for more about this policy.

Here's a few pages from the character generation section. I'm also using something like a point-buy system (called Karma, though that name may change as it sounds too spiritual) for leveling up, such that characters only get a certain amount of points during the level-up process that they use to improve/change their character and these points are used to increase certain aspects of their character. The way I have it worded now it suggests that the character uses their karma points to initiate the skill point shifting process, but that implies they have some sort of choice in the matter, which seems to me that they're more likely to just leave things as they are. I really don't want there to be too much choice in that, rather the only choice should be in which least-used skill points move to which most-used skills. It should be more of an automatic thing and I'll change the text up to reflect that.

How familiar are you with game mechanics similar to what you're describing? Looking over the games I know, I see two variables, one of which has seen a great deal of refinement and variation from the beginning of the hobby, and the other having been effectively absent.

Variable #1 = skill improvement strictly based on skill use. I don't know if BRP (Basic Roleplaying) was the very first to use this, but it was certainly in the first batch of games from the beginning of RuneQuest. If you succeeded with a skill (% or less on d100), then later, you rolled d100 to see if you scored higher than the current skill value. If you did, then it went up by 5%. This system was applied as well to Call of Cthulhu and to a host of other games published by The Chaosium, and influenced a major portion of later designs.

As I mentioned, the basic idea was refined and tweaked a lot. In Stormbringer, for instance, also published by The Chaosium, if you succeeded in the irmprovement check, then you went up by d10%, not a fixed amount. Many games tried to resolve the ambiguity between how many times you succeeded in a given game session or adventure, relative to how often you checked for improvement.

Some interesting variations ... in Legendary Lives (1990/93), you roll for improvement only if you rolled a Catastrophic or an Extraordinary result during play, and you get as many check marks, also called Inspiration Points, as you had roll outcomes which qualified. (The text suggests going up in 1-5 skills per gaming session.) The game is available for free here; the relevant rules are a bit hard to find so I'll point the interested reader to pp. 157-158.

In Forge: Out of Chaos (2000, I think), there are two different types of skills which advance through use. One of the types advances very much like those in BRP. The other type uses a plateau method which is complex to summarize verbally ... the idea is that the skill operates in "levels" of units 1, 2, 3, et cetera, and the % is not used for resolution, but rather more like a jar you fill in order to get to the next level. Interestingly, the roll to improve gets easier as you go along, but the "jar" gets bigger. Again, though, you don't get a chance to improve unless you succeed with the skill.

In Undiscovered (2001), there's such a complex array of tables to account for individual skill improvement, and similar to the above, for different categories of skills, that I can't reproduce it verbally without studying the text again. Suffice to say that the issue was deeply felt by the authors and the method is expected to be a source of direct enjoyment for players.

In Burning Wheel (2003), there's a rather sophisticated chart concerning whether you failed or succeeded, how good you are with the skill, and how hard the check was, such that every skill's history becomes quite distinct and logical during the play-life of the character.

My point is that you have a rich history to compare and draw upon if you want for this issue. The key sub-variables for this part appear to be under what conditions you get to check for improvement (success or success/failure), whether skills fall into various categories with different means of improvement, whether and how the chance to improve changes, and how number of qualifying rolls relates to session relates to adventure, in terms of how many times you actually get to check.

By the way, your point about how only in-play relevant skill use counts for purposes of improvement is standard text for all these games.

Variable #2 - reduction in skill effectiveness via lack of use. You got me on this one - I'm not saying that no RPG has ever done this, but I sure can't think of any. As a minor point, I agree with you that a skill should bottom-out at some % higher than 0. It's up to you to decide what value is low enough to denote "rustiness" without itself being practically no different from 0.

Overall - the really interesting aspect of your design for me is that you're working with a fixed pool of % points which shift around. This is kind of fascinating, speaking as a potential player, because it means I can jack up skills to their max only if I beggar most of my others, and if I want to be pretty good at a lot of stuff, I can only get so good. It allows for some very interesting decisions about who my character will become, to be discovered in play rather than pre-set by a character-category option.